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15 min ago 2 min read
UK-based student rocketry team UCL Rocket (UCLR) has completed the first successful hot-fire test of its seven kilonewtons (kN) cryogenic, regeneratively cooled rocket engine, fuelled by liquid oxygen and isopropyl alcohol.
The successful hot-fire test, held on 24 June, marks a key step in the development and validation of UCLR’s cryogenic rocket engine concept.
UCLR has transitioned from its nitrous oxide-based oxidiser architecture, used in the previous Excelsior engine, to a cryogenic liquid oxygen (LOX) system.
With the new engine, the UCLR team has faced greater engineering challenges, managing higher heat fluxes, more extreme thermal gradients, stricter cleanliness requirements, and additional material compatibility considerations.
Under a hot fire test, the rocket engine remains anchored to the ground and is ignited to test the operational capacity of the propulsion system.
Global additive manufacturing solutions company Eplus3D supported the production and testing of UCLR’s combustion chamber hardware in the liquid rocket engine.
The CuCrZr combustion chamber is designed with 57 internal cooling channels for regenerative thermal management.
Pre-test inspections found that around 33% of the cooling-channel area was blocked by metallic swarf from post-machining. UCLR responded by running the engine at 50% throttle and adding 2% PDMS to reduce heat on the chamber walls.
Despite the reduced cooling capacity, the engine successfully ignited, and the combustion chamber remained intact, with no visible signs of thermal erosion or deformation.
The test builds on UCLR’s previous Excelsior engine programme and provides further data for the development of its cryogenic propulsion technology.
